British Airways has announced a deal with Swiss International Airlines that will see the two companies sharing flights between their two countries.
BA is also to take over eight of Swiss's Heathrow airport take-off and landing slots.
In addition, Swiss - formed following the collapse of Swissair - will enter the Oneworld alliance of airlines of which BA is a founder member.
The two carriers plan to start codesharing on Swiss's Heathrow routes from October 26 in a move that BA says will give both airlines' customers convenient access to worldwide destinations via London and Zurich.
BA's chief executive Rod Eddington said: "I am delighted to welcome Swiss into the Oneworld alliance. This commercial deal will benefit both British Airways and the new Swiss, which has a quality product, network and hub in Zurich which makes it a logical fit to Oneworld in central Europe."
Andre Dose, chief executive officer of Swiss, said: "We are proud to be a member of Oneworld, the world's leading international alliance. Swiss, as well as Oneworld clients, will benefit from the enhanced network and the joint frequent flyer programmes."
The link-up is further evidence of the need, and desire, of airlines to form alliances at a time of mounting financial difficulties for many carriers.
Two big European players - Air France and KLM - are currently involved in talks about a possible major link-up.